Odd readings on RPM gauge

[hgf]

I have a two year old Honda 90. Recently the RPM gauge on the dash shows odd readings. When idling, it may rev up way up, even though the motor is not going any faster. Ditto at speed. Then it will read normally for a long time. There is not a consistant pattern as far as I can tell. The motor runs just fine. I am assuming there is a wire or contact loose somewhere. Anything a non mechanic can check, or is it a trip to the dealer??? Is this urgent? Am I hurting anything as long as I watch my top end revs???

[TOOLMAN 1]

Don't know if this will be of any help but I had a 90hp johnson a few years back that did the same thing and it was the voltage regulator. Had to replace it.Like I said don't know for sure since we are talking about two differant brands and types of motors. Good kuck!